Tracer valve



Nov. 24, 1959 A. ANDERSON TRACER VALVE Filed Aug. 27. 1956 v fm1/n for*e lrzdensoft, w ,I a uw j) jfl/Wwf Patented Nov. 24, 1959 TRACER VALVEAxel Anderson, Rockford, Ill., assigner to Sundstrand Corporation, acorporation 'of Illinois Application August 27, 1956, Serial No. 606,512

4 Claims. (Cl. 251-3) This invention relates to valves and, moreparticularly, to a tracer valve.

It is the general object of this invention to provide a new and improvedtracer valve. l

A more specilic object of this invention isY to provide a new andimproved tracer valve wherein a longitudinally movable valve member isresponsive to lateral pressure applied to a stylus disposedsubstantially in alignment therewith to move the valve member in onedirection.

Another object of this invention is to provide such a tracer valvewherein the valve member isv slidable ina sleeve having a plurality ofliuid ports and passages formed therein, wherein resilient means areprovided to urge the valve member in the other direction and wherein thestylus is carried in a valve stempivotally mounted in the end of thesleeve so that pivotable movement of the valve stem causes movement ofthe valve member to control the ow of liuid through the ports andpassages formed in the sleeve.

Another object of the invention is to provide a new and improved tracervalve of the character describedwherein a pin carried in the valve stemadjacent the pivotal mounting thereof is engageable with a slottedportion of the sleeve so as to prevent rotation of the valve stem andthe stylus with respect to the sleeve, thus insur bodiment of theinvention taken generally along line 1 1` of Fig. 2;

Fig. la is an enlarged fragmentary View of Fig. l show ing-the pivotalconnection between the Valve stem and the retainer;

Fig. lb is an enlarged fragmentary vertical sectional view takengenerally along line 1b`1b of Fig. 1;

Fig. 2 is a horizontal sectional view taken generally along line 2-2 ofFig. l;

Fig. 3 is a top plan view of Fig. 1 with the cover removed;

Fig. 4 is a vertical sectional view on a reduced scale taken generallyalong line 4--4 of Fig. 2; and

Fig. 5 is a vertical sectional view on a reduced scale taken generallyalong line 5 5v of Fig. 2.

While the invention herein described is a preferred embodiment, it isnot intended to limit the invention to the specic form and arrangementshown, it being contemplated that various changes may be made by thoseskilled in the art without departing from the spirit and scope of theappended claims.

Referring to the drawings for a description of a preferred embodiment ofthe invention, the tracer valve in cludes a hollow sleeve or housing 10having a reduced end portion 11. A bore 10 extends through the housing.A transverse passage 12 is adapted to be connected at its outer. end toa source of fluid under pressure, and at its inner end connects with anannular groove 16 around the central position of the bore 10. Atransverse passage 13 is adapted to be connected at its outer end to alluid reservoir and at its inner end to anV annular groove 17 in thebore 10 spaced below the groove 16. A pair of transverse passages 14 and15 are adapted to be connected at their outer ends to a cylinder andpiston device to be controlled. As shown in the drawings, the passages14 and 15 extendthrough` the housing wall andopen into the bore 10 onopposite sides ofthe groove 16. An internal annular groove 18 formed inthe bore 10 is also adaptedy to be connected to the fluid reservoirthrough a lateral bore 19'and ablongitudinal bore 20 (both of which havetheir outer ends plugged), as shown in Fig. 4.

In order to control the ow of fluid through the passages described, avalve member 25 having lands 26, 27 and 28 is slidable in the bore 10.As shown in Fig. l, the lands are spaced apart the same as the groovesl18, 16 andV 17 respectively. Land 27 serves to control the flow of fluidfrom pressure passage 12 to the cylinder passages 14 and 15, whereas thelands 26 and 2S control the return of fluid from the cylinder passagesto the reservoir passage 13. Movement of the valve member25 iscontrolledby a valve stem 29 disposed in the reduced` end portion 11 of thehousing and universally pivotally mounted in a retainer or mountingmember 30'threadably mounted in the end of the housing. The valve stem29 has a semi-spherical surface 31 riding on an internal conical surface32 formed on the retainer 30, as best shown in Fig. la. The valve stem29 is pivotable upon a lateral pressure being applied to a stylus 33which eX- tends axially from the valve stem 29 and is secured therein bya set screw 34. To convert the pivotal movement of the valve stem 29 tolongitudinal movement of the valve member 25, a single relatively largeball 35is disposed between adjacent ends of the valve member 25 andthevalve stem 29, the ball 35 being disposed in opposing conicalrecesses 36 and 37 formed respectively in the ends of the valve member25 and the valve stem 29.

The valve member 25 is constantly urged downwardly by a relatively weakspring 39 which is mounted in a |bore 40 formed in the upper end of thevalve member. 25, the spring 39 acting against a snap ring 41 mounted inthe bore 40. and against a valve cap y42 secured against the upper endofthe housing 10 by bolts 43.

During normal tracing operation, the valve memberV 25 is controlledsolely by the spring 39 and the stylus 33.

When the stylus 33 reaches a depression lin a template (not shown) thespring 39 is operable to urge the valve member 25 downwardly so as toalign the valve stem 29 with the Valve member 25, as shown in Fig. l,and thus shift valve member to the olf-center position whereinl pressurefluid from groove 16 flows out the cylinder passage 14 (which inaccordance with well known practice would cause the piston in thecylinder to move the tracer valve toward the template). When the stylus33 reaches a projecting portion of the template, it will be pivoted` toa greater angle than that of its neutral position so as to shift thevalve member 25 upwardly and thus pass pressure uid from groove 16 tocylinder passage 15 and cause shift of the tracer valve away from thetemplate.

It is believed apparent with such a valve construction that if the valvestem 329 is freely rotatable in the retainer 30, the accuracy of thetracer valve would be greatly decreased should the stylus 33 ever becomebent out of alignment with the valve stern 29. Instead of the valvestern 29 pivoting purely in response to the surface variations in thetemplate, any rotation of the olf-center stylus would result inerroneous pivoting movement of the valve stern 29. To insure maximumaccuracy of this tracer valve, means have been provided to preventrotation of the valve stem 29 in the retainer 30 while permittinguniversal pivoting movement of the valve stern 29. As shown in Figs. land 1b, this means includes a pin 44 which is tightly fitted in a bore45 formed in the valve stern 29 and which has end portions 46 extendingradially from the valve sterny 29 and engageable in vertical slots 47formed in the retainer 30.

In order to provide means for rapidly retracting the valve member 25 toan upper position in which pressure uid flows out cylinder passage 15, asolenoid indicated generally at 48 is provided. The solenoid 48 includesa block 49 having an integral plate 49a secured against the valve cap 42by bolts 42a. The block 49 has a bore 50 formed therein in alignmentwith the valve member 25 and a cylindrical coil 51 mounted on the block49 with a plunger 52 disposed therein. The end of the plunger 52 abutsagainst a push pin 53 slidable in the bore 50 which in turn abutsagainst the end of a rod member 54 which is slidably mounted in a bore55 formed in the valve cap 42 and has a head portion 56 held looselycaptive in the bore 40 in the end lof the valve member 25 by the snapring 41. A relatively strong compression spring 57 acting between thevalve cap 42 and a spring retainer 58 pinned to the rod member 54 actsto move the valve member 25 upwardly when the solenoid is de-energizcd.As seen in Fig. 3, leads 69 for the solenoid coil 51 pass throughopenings in the valve cap 42 and into a flexible conduit 70 mounted inan opening in the valve cap 42.

During normal operation of the tracer valve, the solenoid 48 isenergized thus holding the plunger 52 downwardly of the coil 51 as shownin Fig. 1, and maintaining the rod member 54 in the position shown, thusneutralizing the action of the spring 57 and allowing the valve member25 to be controlled solely by the stylus 33 and the spring 39. When itis desired to shift the valve member 25 upwardly, independently ofactuation of the stylus 33, the solenoid 48 is de-energized, thuspermitting the spring 57 to move the rod member 54 and plunger 52upwardly so that the head 56 of the rod member 54 engages the snap ring41 and lifts the valve member 25 upwardly.

As shown in Fig. l, a cover member 60 enclosing the solenoid 48 isfitted over the valve cap 42 and against the housing 1G so as to providean extension of the housing 10. As it may be desirable to advance thestylus 33 without energizing the solenoid 48 as when setting up a job, amanual button 61 is mounted in an opening in the end of the cover member60. When the button is depressed against the plunger 52, the rod member54 is moved downwardly so as to neutralize the spring 57 and allow thevalve member 25 to be controlled by the spring 39, thus moving thestylus 33 to the position of Fig. l.

As shown in Fig. l, the valve member 25 is hollow, having a relativelylarge longitudinal bore 63 formed therein communicating at one end withthe bore 40 and at the other end with the conical recess 36 through Vareduced passage 64. By hollowing out the valve member 25, its weight issubstantially reduced so as to reduce serious shocks when the valveoscillates on high frequency. which may be a common occurrence in tracervalves. The hollow valve member 25 also permits fluid leaking around thevalve member 25 to reach the single ball 35 and the valve stem pivotingsurfaces 31 and 32 to provide lubrication of these moving parts.

vA vacuum opening 66 (shown 90 out of position in Fig. 1) formed in theend of the reduced end portion 11 of the housing 10 communicates througha chamber 67 in the reduced end portion 11 of the housing 10 with alongitudinally extending passage 68, best shown in Figs. 2 and 5, formedin the housing 10 and opening at the other -end between the end of thehousing 10 and the valve cap 42. This vacuum system is adapted to beconnected to a vacuum device, at the opening 66, so that excess fluidmay be drained from the valve to prevent a build up of uid pressure ateither end of the valve member 25 which could affect the operationthereof.

Thus there is disclosed a compact and simplified tracer valve havingmeans for rapidly reh'acting the valve member when desired, whichcomprises a relatively small number of parts and which is veryefficient, sensitive and accurate in operation. This tracer valve alsoprovides automatic retraction of the stylus and an associated cuttingtool in the event of a power failure.

I claim:

1. A tracer valve, comprising, a valve housing having a longitudinalvalve bore, a generally cylindrical valve member slidable in the valvebore and having external formations to control the ow of uid betweenfluid passages communicating with the valve bore and having a Vcentrallongitudinal recess therethrough providing a hollow, light weightconstruction, a template engaging stylus movably mounted in one end ofthe housing for effecting longitudinal movement of the valve member inone direction, away from said one lend of the housing, an end capclosing the other end of the valve housing, a snap ring positioned inthe valve member recess, a first spring bearing against the end cap andthe snap ring urging the valve member in the opposite direction, andselectively operable means independent of the valve member for movingthe valve member in said one direction in opposition to said firstspring including a valve actuating rod reciprocable in the end caprelative to the valve member, said rod having an inner end positioned inthe valve member recess and an outer end positioned outside the housing,a head on the inner end of the rod engageable with the snap ring formoving the valve stern in said one direction, a second spring strongerthan the first spring connected to the outer end of the rod for movingthe rod in said one direction to engage the head and snap ring tothereby move the valve member in said one direction in opposition to thelirst spring, and means engageable with the rod adjacent the outer endthereof for moving the rod in said opposite direction to compress thesecond spring and disengage said head and snap ring.

2. A tracer valve, comprising, a valve housing having a longitudinalvalve bore, a valve member slidable in the valve bore for controllinguid flow between uid passages communicating with the valve bore, atemplate engaging stylus movably mounted in one end of the housing foreffecting longitudinal movement of the valve member in one direction,away from said one end of the housing, an end cap closing the other endof the housing, a first spring bearing between the end cap and the valvemember urging the latter in the opposite direction, and selectivelyoperable means separate from the valve member for moving the valvemember in said one direction in opposition to said first spring,including a rod longitudinally reciprocable in the end cap relative tothe valve member and having an outer end outside the housing and aninner end within the housing engageable with the valve member to movethe valve member in said one direction, a second spring stronger thanthe first bearing against the end cap and the outer end of the rodurging the rod in said one direction, a solenoid having a reciprocableplunger movable against the rod when the solenoid is energized tocompress the second spring and disengage the inner end of the rod fromthe valve member to free the valve member for control by the firstspring and the stylus, said solenoid when deenergized releasing theplunger to permit movement of the rod and valve member in said onedirection under urge of the second stronger spring.

3. A tracer valve, comprising, a valve housing having a longitudinalvalve bore, a generally cylindrical valve member slidable in the valvebore and having external formations to control the ow of fluid betweenfluid passages communicating with the valve bore and having a centrallongitudinal recess therethrough providing a hollow, light weightconstruction, a template engaging stylus movably mounted in one end ofthe housing for eifecting longitudinal movement of the valve member inone direction, away from said one end of the housing, an end cap closingthe other end of the valve housing, a snap ring positioned in the valvemember recess, a spring bearing against the end cap and the snap ringurging the valve member in the opposite direction, and selectivelyoperable means independent of the valve member for moving the valvemember in said one direction in opposition to said spring including avalve actuating rod reciprocable in the end caprelative to the valvemember, said rod having an inner end positioned in the valve memberrecess and an outer end positioned outside the housing, a head on theinner end of the rod engageable with the snap ring for moving the valvestem, a head on the outer end of the rod, a second spring stronger thanthe iirst bearing against the outer head and the end cap urging the rodin said one direction, a solenoid having a reciprocable plunger movableagainst the outer end of the rod on energization of the solenoid to movethe rod in said opposite direction compressing the second spring anddisengaging the inner head and snap ring to free the valve member forcontrol by the first spring and the stylus, the solenoid whendeenergized releasing the plunger to permit movement of the rod andvalve member in said one direction under urge of the second strongerspring, and a manually depressible button for moving the solenoidplunger against the rod to compress the second spring when the solenoidis deenergized.

4. A tracer valve comprising, a valve housing having a longitudinal boretherein, a valve member slidable in the bore for controlling fluid owbetween fluid passages communicating with the bore, a template engagingstylus movably mounted in one end of the housing for eectinglongitudinal movement of the valve member in one direction, away fromsaid one end of the housing, a rst spring means urging the valve memberin the opposite direction, and selectively operable means separate fromthe valve member for moving the valve member in said one direction inopposition to said rst spring means, including an actuating rodlongitudinally reciprocable in the opposite end of the housing relativeto the valve member and having an outer end outside the housing and aninner end within the housing having a lost motion connection with thevalve member to move the latter in said one direction, second springmeans stronger than the rst urging the rod in said one direction, asolenoid having a plunger movable against the outer end of the rod whenthe solenoid is energized to overcome the second spring means anddisengage the inner end of the rod from the valve member for control bythe first spring means and the stylus.

References Cited in the le of this patent UNITED STATES PATENTS2,083,774 Campbell June 15, 1937 2,586,654 Hoelscher Feb. 19, 19522,726,582 Roehm Dec. 13, 1955 2,731,980 Diefenderfer Jan. 24, 19562,743,584 Rosebrook May 1, 1956 FOREIGN PATENTS 354,819 Germany 1.... of1922 503,968 Canada of 1954

